xiv ILLUSTRATIONS 



FACING PAGE 



Long-tailed vizcacha of the high Andes 410 



Short-tailed vizcacha of the Argentine lowlands 410 



Rice-fields at the foot of the Andes Mountains, Sarmientos .... 416 



MAPS 



Sketch map of the south-central part of the Amazon drainage system . 241 



Routes taken by the author in his South American explorations 



At end of the volume 



